Improvement in sewing-machines



2 Sheets-Sheet l.

R. WELCH. SEWING MACHINEI No. 34,081. Patented Jan, 1862.

2 Sheets-Sheet 2.

R. WELCH. SEWING MACHINE.

No. 34.081, .Patented Jan. 7, 1862.V

Wnesses,

UNITED STATES PATENT OFFICE.

ROBERT WELCH, OF FRA-NKFORD, PENNSYLVANIA.

'IMPROVEMENT INy SEWINGvMACHINES.

Specilication forming pal-t of Letters Patent No. 34,08 l. datedJarnlary T, 186') ,'lo all yzr/lo'm, 'it may concern.-

Be it known that I, ROBERT WELCH, of Frankford, in the county ot'Philadelphia and State ot' Pennsylvania, have invented a new and usefulImprovementin Seiviiig-lllacliines; and l do hereby declare that thefollowing is a full, clear, and exact description of the same, referencebeing had totheaccompanying drawings, forming part of thisspecilication, in which- Figure lis an elevation of that end of asewingmacl1ine farthest from the needle, Fig. 2 is a vertical section ofthe machine at right angles to Fig. l.

`Similar letters of reference indicate corresponding parts in bothfigures.

My invention relates to the use of a threadfceding apparatus for feedingthe thread to the performing-needle, so combined with the clothfeedingapparatus that the quantity of thread supplied foreach stitch willalways be in proportion to or will correspond with the length 0f thatstitch; and the invention particularly consists in a device, hereinafterdescribed, which adapts the improvement to various descriptions of feedin common use and admits of ready adjustment to suit various thicknessesof material being sewed.

To enable those skilled in the art' to make and use my invention, I willproceed to describe its construction and operation.

A is the bed of the machine. B is the stationary arm, U lthe presser, Dthe needlebar, and E tle needle-operating lever, all constructet. andapplied as in many other Wellknown sewing-machines.

F is the main shaft, and Gr the shaft of the cloth-feed wheel H,arranged parallel with each other in bearings below the bed-plate, themain shaft carrying a needle operating` cam, I, a shuttle-operating cam,J, and a cranlror eccentric wrist, a, for producing.,r Vthe feed movement, and the feed-shaft carrying, besides the feed-wheel, a pulley, K.

L is-a shaft arranged between centers in standards b b, above the bed A,in a position Vparallel with the main and feed shafts for the purpose ofcarrying a cone, M, having severall grooves, c c, running round itsperiphery, the said cone being either made of the same piece of metalwith the said shaft or being otherwise constructed a'nd secured lirmlyto the shaft concentric therewith. This many grooved cone constitutesthe principal portieri ofthe thread-feeding apparatus, as will bepresently explained. 'lhe shaft L has also formed upon or secured to itagrooved pulley, r1,i'or the reception of a band, e, to run round it andround the pulley K of the feedshaft, and the said shaft L has alsosecured to it a ratchet-wheel,

f, and has tted loosely to ita lever, N, carrying a pawl, g, which worksin the said ratchetwheel. rlhe lever N is connected by a rod, 0, withthe crank-wrist a, from which, when. the machine is in operation, thesaid lever derives an oscillating movement snicient to carryits pawlover one or more teeth of the ratchetwheel, by which means it is made toimpart to the shaft L and cone M au intermittent rotary motion, givingthem one movement for every operation .of the needle and shuttle, andthe shaft L, by means of the pulley d, band e, and pulley K, is made toimpart a lcorresponding movement to vthe feed-shaft for the purpose otfeeding the cloth. lt is a slot provided in the lever N for shifting theconnection `of' the rod O to vary `the feed.

P is a movable tightening-pulley for tight ening the band e. A pairofspurgears may be substituted for the bande and pulleys d and K, and inthat case it will be desirable to arrange the shaft L nearer to thefeed-shaft than is represented in the drawings.

The spool R, carrying the needle .thread, may be arranged in anyconvenient relation to the cone M for the thread to pass once or moretimes round the said'cone, in one of the grooves thereof, on its way tothe needle n. I have represented the said spool as placed upon a pin, i,secured in the table of the machine. The thread is directed from thesaid cone to the needle n by guidesj 7c l, arranged in any suit-l ablemanner, according to the -form and construction of the machine. Thethread is represented in red color.

The thread in passing round the cone Ml is subject to such a. degree offriction that it will not slip thereon under any ot' the ordinarycircumstances of the operation ot the machine, but will be drawn oli`the spool and fed toward the needle in every movement ot' the said coneproduced by the action of the wrist a, rod O, lever N, pawl g, andratchet-wheelf, as hereinbel'ore described, the quantity thus drawn fromthe spool being greater or less, according as the movement of the pawl gis greater or less. The said quantity must always correspond with thefeed movement of the cloth, for' the shaft G of the cloth-feed wheel isdriven by the shaft L of the cone M, and as no thread passes the coneexcept While thevfeed takes place, the tension of the needlefthread inthe several stitches must be uniform if the thickness of the cloth isuniform. y The thread-feed and the cloth feed operating simultaneouslycauses the quantity to be regulatedfcr every separate stitch, so that ifthe cloth-feed is altered the thread-feed is altered to accommo-v datethe very first stitch made after the alteration.A `In case ot' a suddenincrease of the thickness of the cloth, as in the crossing of a seam,the thread will slip on the cone. The several grooves in the cone are toadapt the operation to diierent thicknesses of cloth, rnorelorlessthread being fed, accordingr as it passes round a larger or smallerportion ofthe cone. In a machine which would; always be required to, sewthe same thickness of cloth a simple groovedor plain cylindrical rollermay be used in place of and would be equivalent to a cone with manygrooves.

will remark that, though the sewing-niachine represented is ashuttle-machine, my invention is not limited in its application to thatclass of machines, but may be used in all kinds of sewing-machines. WhatI claim as my inventiomand desire to secure by Letters Patent, is-

1. Feeding the thread to the needle of the .sewing-machine by means of ashaft, L, ro-

